1. Field of the Invention
The present invention relates to a disc cartridge having encased therein a disc-shaped recording medium such as an optical disc, magneto-optical disc or the like.
2. Description of the Related Art
As the disc-shaped recording medium, a disc cartridge having a magneto-optical disc for example encased therein has been proposed.
Referring now to FIG. 1, there is schematically illustrated a conventional disc cartridge in the form of a perspective view. In FIG. 1, the disc cartridge is generally indicated with a reference 201. The disc cartridge 201 includes a cartridge body 206 consisting of a pair of upper shell 211 and lower shell 212 assembled to each other. These upper and lower shells 211 and 212 are made of a resin material. Each of the upper and lower shells 211 and 212 of the cartridge body 206 has formed therein an access opening 215 having a generally rectangular shape. The access openings 215 are opposite to each other. Thus, a part of the recording area of the magneto-optical disc 205, extending between lead-in and lead-out areas, is exposed outside through the openings 215 for data read and write.
The lower shell 212 of the cartridge body 206 has formed therein adjacent or next to the access opening 215 a drive opening 217 through which a disc table (not shown) of a disc drive mechanism which drives to rotate the magneto-optical disc 205 comes into the cartridge body 206.
Further, the cartridge body 206 has a shutter member 220 mounted thereon as shown in FIG. 1. Normally, the shutter member 220 covers or closes the access openings 215 and drive opening 217. When the disc cartridge 201 is loaded into a recorder/player, the shutter member 220 will be moved and thus the access and drive openings 215 and 217 will be opened. The shutter member 220 consists of an upper shutter portion which closes and opens the access openings 215 in the upper shell 211, a lower shutter portion which closes and opens the access openings 215 and drive opening 217 in the lower shell 212, and a connection to which each of the upper and lower shutter portions is connected at one end thereof. Further, the cartridge body 206 has disposed therein an elastic member (not shown) to force the upper shutter portion of the shutter member 220 in a direction in which the upper shutter portion closes the access openings 215 and drive opening 217.
When the disc cartridge 201 constructed as in the above is loaded into the recorder/player, the shutter member 220 is moved by a shutter open/close member of the recorder/player to open the access openings 215 and drive opening 217. The disc table of the disc drive mechanism (not shown) of the recorder/player comes into the disc cartridge through the drive opening 217 to rotate the magneto-optical disc 205 in the disc cartridge 201, while the write/read head of the recorder/player comes into the disc cartridge 201 through the access openings 215 to write/read information to/from the magneto-optical disc 205.
In the aforementioned conventional disc cartridge 101, however, since the front end thereof at which the disc cartridge 201 is first inserted into and removed from the recorder/player is formed straight perpendicularly to the direction of insertion into the recorder/player and both the main sides of the cartridge body 206 are formed generally square, it is difficult to easily know the correct inserting direction of the disc cartridge 201 from its appearance.
Therefore, the conventional disc cartridge 201 is likely to be inserted in a wrong direction into the recorder/player.
In the conventional disc cartridge 201, the shutter member 220 is moved under the action of only the force of the elastic member to the position where it closes the access openings 215 and drive opening 217. Since in the conventional disc cartridge 201, the shutter member 220 can thus be moved easily to the open position against the force of the elastic member, there is a likelihood that the shutter member 220 is inadvertently opened.
It is therefore an object of the present invention to overcome the above-mentioned drawbacks of the prior art by providing a disc cartridge having a body whose front end to be opposite to a recorder/player may be designed to have an arbitrary shape for easy knowing of a correct direction of insertion into the recorder/player and provided with a shutter open/close mechanism suitable for use with the cartridge body having the arbitrarily shaped front end.
The above object can be attained by providing a disc cartridge including according to the present invention a disc-shaped recording medium; a cartridge body having formed therein a disc compartment to house the disc-shaped recording medium; an access opening formed in the cartridge body and through which a part of the recording area of the disc-shaped recording medium, extending between lead-in and lead-out areas, is exposed outside for data read and write; and a shutter member provided movably to open and close the access opening. The disc cartridge also includes a shutter open/close mechanism having a guide recess formed in a main side the of the cartridge body to be oblique in relation to the width of the cartridge body to support the shutter member movably, a guide member supporting the shutter member and movably engaged in the guide recess, an operating member to move the guide member, a transmission member linking the guide member and the operating member to each other to transmit an operating force from the operating member to the guide member, and support surfaces formed on the cartridge body to support the operating member movably. Further, the disc cartridge includes a shutter locking mechanism disposed on the lateral side of the cartridge body to inhibit the shutter member from moving.
In the disc cartridge constructed as in the above, since the shutter member is inhibited from moving by the shutter locking mechanism, it is held to close the access opening.
In the above disc cartridge according to the present invention, the guide recess formed on a main side of the cartridge body to be oblique relative to the width of the cartridge body allows the front end of the cartridge body at which the disc cartridge is first inserted into the recorder/player to be formed in an arbitrary shape for easily knowing a correct direction of insertion in the recorder/player, so that the disc cartridge can be prevented from being inserted in a wrong direction into the recorder/player. Also, the shutter locking mechanism provided matching the cartridge body whose front end is formed in the arbitrary shape permits to lock and hold the shutter member in positions where it opens and closes the access opening.
These objects and other objects, features and advantages of the present intention will become more apparent from the following detailed description of the preferred embodiments of the present invention when taken in conjunction with the accompanying drawings.